The present invention relates to an electric machine with a cylindrical magnet arrangement and with a cooling device for cooling the magnet arrangement. The present invention relates, furthermore, to a corresponding method for cooling an electric machine.
Electric machines of a large type of construction, above all, are to be equipped, as a rule, with a cooling system. The customary way of supplying coolant is to introduce it directly into the interior of the electric machine. The coolant mostly enters one of the two bearing shields. The coolant normally used is air. The air conducted into the interior is distributed according to the space conditions. The flow through cooling channels, which are provided, for example, in the laminated core of the electric machine, takes place according to the flow resistances which arise. In many motors, it is necessary to position the entry of air into the region of the bearing shields, with the result that appropriate measures must be taken to achieve a sufficient cooling effect.